JP2012501091A - Material for organic photoelectric element and organic photoelectric element including the same - Google Patents

Abstract

Disclosed is an organic photoelectric device material containing an asymmetric compound of Formula 1 and an organic photoelectric device containing the same. The organic photoelectric device material can serve as a hole injection material, a hole transport material, a light emitting material, or an electron injection material and / or an electron transport material in an organic photoelectric device such as an organic light emitting diode. It can also serve as a light emitting host with an appropriate dopant. When the material is applied to an organic photoelectric element such as an organic light emitting diode, an organic photoelectric element excellent in life, efficiency, driving voltage, electrochemical stability and thermal stability can be obtained.
[Selection] Figure 1

Description

  The present invention relates to a material for an organic photoelectric device and an organic photoelectric device including the material. In more detail, this invention relates to the organic photoelectric element material which can improve the lifetime, efficiency, drive voltage, electrochemical stability, and thermal stability of an organic photoelectric element, and an organic photoelectric element containing the same.

  An organic photoelectric device is an element that requires charge exchange between an electrode and an organic material using holes or electrons.

  Organic photoelectric elements can be classified as follows according to the operating principle. In the first organic photoelectric device, exciton is generated in the organic material layer by photons from an external light source, the exciton is separated into electrons and holes, and the electrons and holes are passed through different electrodes. It is an electronic device that is driven by moving as a source (voltage source).

  In the second organic photoelectric device, voltage or current is applied to at least two electrodes to inject holes or electrons into the organic material semiconductor located at the interface between the electrodes, and the devices are driven by the injected electrons and holes. Electronic device.

  Examples of organic photoelectric elements include organic light emitting diodes (OLEDs), organic solar cells, organic photoconductor drums, organic transistors, organic memory elements, and the like, which are hole injection materials or hole transports. A material, an electron injection material or an electron transport material, or a light emitting material is required.

  Hereinafter, the organic light emitting diode will be specifically described mainly. In the organic photoelectric element, a hole injection material or a hole transport material, an electron injection material or an electron transport material, or a light emitting material acts on the same principle.

  2. Description of the Related Art Organic light emitting diodes (OLEDs) have attracted attention in recent years as demand for flat panel displays has increased. In general, organic light emission refers to conversion of electrical energy into light energy using an organic substance.

  Such an organic light emitting diode is an element that converts electric energy into light by applying an electric current to an organic light emitting material, and a functional organic material layer is inserted between an anode and a cathode. It has a structure. The organic material layer may be a multilayer including different materials, for example, a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer, an electron transport layer, in order to increase the efficiency and safety of the organic light emitting diode (ETL), an electron injection layer (EIL), and the like.

  In such an organic light emitting diode, when a voltage is applied between the anode and the cathode, holes are injected from the anode and electrons are injected from the cathode into the organic material layer. The generated excitons move to the ground state and generate light having a specific wavelength.

  In 1987, Eastman Kodak first developed an organic light-emitting diode containing a low-molecular aromatic diamine and an aluminum complex as a light-emitting layer forming material (Applied Physics Letters, 51, 913, 1987). . In 1987, C.I. W. Tang et al. First reported a practical device as an organic light emitting diode (Applied Physics Letters, 512, 913-915, 1987).

According to the above document, the organic layer is formed by laminating a thin film of a diamine derivative (hole transport layer (HTL)) and a thin film of tris (8-hydroxy-quinolate) aluminum (Alq ₃ ). Has a structured.

  Recently, it has become known that not only fluorescent light-emitting materials but also phosphorescent light-emitting materials can be used as light-emitting materials for organic light-emitting diodes (DF O'Brien et al., Applied Physics Letters, 74 3,442). -444, 1999; MA Baldo et al., Applied Physics letters, 75 1, 4-6, 1999). In such a phosphorescent material, after an electron transitions from a ground state to an excited state, singlet excitons undergo non-radiative transition to triplet excitons through intersystem crossing, Light is emitted by a mechanism in which triplet excitons transition to the ground state and emit light.

  As described above, in the organic light emitting diode, the organic material layer includes a light emitting material and a charge transport material such as a hole injection material, a hole transport material, an electron transport material, and an electron injection material.

  The light emitting materials are classified into blue, green, and red light emitting materials according to the light emission colors, and yellow and orange light emitting materials for emitting light that is further improved to a natural color.

  On the other hand, when only one material is used as the light emitting material, the maximum emission wavelength shifts to the long wavelength side due to intermolecular interaction, the color purity is lowered, or the efficiency of the device is lowered due to the light emission quenching effect. Thus, a host / dopant system may be used as the luminescent material to improve color purity and increase luminous efficiency and stability through energy transfer.

  In order for the organic light emitting diode to fully exhibit the above-described excellent characteristics, the material constituting the organic material layer, such as a hole injection material, a hole transport material, a light emitting material, an electron transport material, an electron injection material, a host and There is a need for luminescent materials such as dopants to be stable and have good efficiency. However, until now, the development of materials for forming organic material layers for organic light emitting diodes has not been sufficiently developed, and therefore new materials are required. Such material development is similarly required for the other organic photoelectric elements described above.

  Exemplary embodiments of the present invention can serve as hole injection materials, hole transport materials, light emitting materials, or electron injection materials and / or electron transport materials, and serve as light emitting hosts with suitable dopants. It provides a novel material that can also fulfill.

  Another embodiment of the present invention provides an organic photoelectric device that includes the material for an organic photoelectric device and has improved lifetime, efficiency, driving voltage, electrochemical stability, and thermal stability.

  The embodiments of the present invention are not limited to the above technical problems, and those skilled in the art can understand other technical problems.

  According to one embodiment of the present invention, a material for an organic photoelectric device including an asymmetric compound represented by the following chemical formula 1 is provided.

In Formula 1,
Ar ₁ is selected from the group consisting of hydrogen and a substituted or unsubstituted aryl group, provided that when Ar ₁ is a substituted aryl group, the substituent of Ar ₁ is not the same as Ar ₂ ;
Ar ₂ and Ar ₃ are each independently a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 2 to 30 carbon atoms, and Selected from the group consisting of substituted or unsubstituted heteroarylamine groups having 2 to 30 carbon atoms;
L ₁ and L ₂ are each independently selected from the group consisting of substituted or unsubstituted phenylene, substituted or unsubstituted naphthylene, and substituted or unsubstituted anthracene;
m and n are integers of 1 to 4.

  According to another embodiment of the present invention, there is provided an organic photoelectric device including an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode. The organic thin film layer includes the organic photoelectric element material.

  According to a further embodiment of the present invention, a display device including the organic photoelectric device is provided.

  In the following, further embodiments of the invention will be described in detail.

  The material for an organic photoelectric device according to an embodiment of the present invention has an asymmetric structure with respect to the pyrimidine core. Such an asymmetric structure including a pyrimidine core has enhanced amorphous characteristics and can thereby suppress crystallization. Therefore, the lifetime characteristics of the organic photoelectric element can be improved when the organic photoelectric element is driven. Therefore, an organic photoelectric device excellent in efficiency, driving voltage, electrochemical stability and thermal stability is provided.

  A novel material according to an embodiment of the present invention plays a role of a hole injection material, a hole transport material, a light emitting material, or an electron injection material and / or an electron transport material in an organic photoelectric device such as an organic light emitting diode. It can also be applied to the role as a light emitting host with an appropriate dopant.

1 is a cross-sectional view illustrating an organic light emitting diode including a compound according to various embodiments of the present invention. 1 is a cross-sectional view illustrating an organic light emitting diode including a compound according to various embodiments of the present invention. 1 is a cross-sectional view illustrating an organic light emitting diode including a compound according to various embodiments of the present invention. 1 is a cross-sectional view illustrating an organic light emitting diode including a compound according to various embodiments of the present invention. 1 is a cross-sectional view illustrating an organic light emitting diode including a compound according to various embodiments of the present invention.

  6 is a graph showing differential scanning calorimetry (DSC) measurement results for the compound according to Synthesis Example 1. FIG.

<Explanation of symbols indicating main elements in the figure>
100: Organic photoelectric element,
110: cathode,
120: anode,
105: Organic thin film layer,
130: light emitting layer,
140: hole transport layer (HTL),
150: electron transport layer (ETL),
160: an electron injection layer (EIL),
170: hole injection layer (HIL),
230: Light emitting layer + electron transport layer (ETL).

  Hereinafter, exemplary embodiments of the present invention will be described in detail. However, these embodiments are merely examples, and the present invention is not limited thereto.

  In this specification, the term “substituted” means an alkyl group having 1 to 30 carbon atoms, a heteroalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, or 6 carbon atoms unless otherwise defined. A group substituted with at least one substituent selected from the group consisting of an aryl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, a fluoro group, and a cyano group.

  As used herein, the term “hetero”, unless otherwise defined, contains 1 to 3 heteroatoms containing N, O, S, P, or Si in the ring, with the remainder being carbon. Means things.

  According to one embodiment of the present invention, a material for an organic photoelectric device including an asymmetric compound represented by the following chemical formula 1 is provided.

In Formula 1,
Ar ₁ is selected from the group consisting of hydrogen and a substituted or unsubstituted aryl group, provided that when Ar ₁ is a substituted aryl group, the substituent of Ar ₁ is not the same as Ar ₂ ;
Ar ₂ and Ar ₃ are each independently a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 2 to 30 carbon atoms, and Selected from the group consisting of substituted or unsubstituted heteroarylamine groups having 2 to 30 carbon atoms;
L ₁ and L ₂ are each independently selected from the group consisting of substituted or unsubstituted phenylene, substituted or unsubstituted naphthylene, and substituted or unsubstituted anthracene;
m and n are integers of 1 to 4.

In Formula 1, Ar ₁ is preferably an aryl group or an aryl group having an aryl substituent. Examples of the aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, and a chrysenyl group.

Ar ₁ is an alkyl group having 1 to 30 carbon atoms, a heteroalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an alkoxy group having 1 to 30 carbon atoms. And a substituent selected from the group consisting of a fluoro group and a cyano group. Examples of the aryl group include an aryl group selected from the group consisting of a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, and a chrysenyl group, and examples of the heteroalkyl group include An alkylsilyl group. However, the aryl group and heteroalkyl group are not limited thereto.

When Ar ₁ is a substituted aryl group, the substituent of Ar ₁ is not the same as Ar ₂ . When Ar ₁ is a substituted aryl group and the substituent of Ar ₁ is not the same as Ar ₂ , an asymmetric structure based on the pyrimidine core is obtained. The material for an organic photoelectric device having such an asymmetric structure suppresses crystallization, so that the life characteristics of the organic photoelectric device can be improved.

In the chemical formula 1, the heteroaryl group represented by Ar ₂ and Ar ₃ includes an imidazolyl group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a triazolyl group, a pyridinyl group, a pyridazine group, a quinolinyl group, an isoquinolinyl group, an acridyl group, Examples include imidazopyridinyl group and imidazopyrimidinyl group.

Examples of the heteroarylamine group represented by Ar ₂ and Ar ₃ in Chemical Formula 1 include a diphenylamine group, a dinaphthylamine group, a dibiphenylamine group, a phenylnaphthylamine group, a phenyldiphenylamine group, a ditolylamine group, and a phenyltolylamine group. Carbazoyl group, triphenylamine group, dipyridylamine group and the like.

In the chemical formula 1, each of the substituents represented by Ar ₂ and Ar ₃ may be substituted or unsubstituted. When Ar ₂ and Ar ₃ are substituted, these are alkyl groups having 1 to 30 carbon atoms, heteroalkyl groups having 1 to 10 carbon atoms, cycloalkyl groups having 3 to 30 carbon atoms, and 6 to 30 carbon atoms. The aryl group, an alkoxy group having 1 to 30 carbon atoms, a fluoro group, and a cyano group may be substituted. Examples of the aryl group include an aryl group selected from the group consisting of a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, and a chrysenyl group, and examples of the heteroalkyl group include An alkylsilyl group. However, the aryl group and heteroalkyl group are not limited thereto.

In Formula 1, L ₁ and L ₂ are preferably phenylene.

The compound of Formula 1 according to the present invention includes a pyrimidine core and a substituent of Ar _{1 to} Ar ₃ . Pyrimidine is an aromatic compound and has an electronic structure like benzene. This pyrimidine has thermal stability or relatively high oxidation resistance, but asymmetric compounds can be synthesized by the difference in reactivity to the 2-, 4-, and 6-positions.

  According to one embodiment, the pyrimidine core moieties are substituted with non-identical substituents to form an asymmetric structure. In the pyrimidine core structure having an asymmetric substituent, the amorphous characteristics are enhanced and crystallization is suppressed, and the lifetime characteristics are improved when the organic photoelectric device is driven. On the other hand, a symmetric compound having the same substituent is easily crystallized, which may shorten the life characteristics of the organic light emitting diode.

A variety of substituents (Ar _{1 to} Ar ₃ ) are introduced into the pyrimidine having the above characteristics to impart necessary characteristics to the organic photoelectric device.

For example, a thermally and electrically stable n-type material is synthesized by introducing substituents having n-type characteristics such as pyridinyl group, quinolinyl group, and isoquinolinyl group into Ar ₂ and Ar _3. P-type materials can be synthesized by introducing substituents having p-type properties. In addition, by introducing both an n-type substituent and a p-type substituent, an amphiphilic material having not only the n-type but also the p-type characteristics can be provided.

  The n-type characteristic means the property of the conductive characteristic according to the LUMO level so as to have an anion characteristic due to electron generation. The p-type characteristic means the property of the conductive characteristic according to the HOMO level so as to have a cation characteristic due to hole generation.

  The compound represented by Formula 1 may further enhance the overall molecular properties to n-type or p-type by introducing various substituents. That is, when a specific substituent is introduced into the substituent portion in Chemical Formula 1 and the characteristic of the compound of Chemical Formula 1 becomes stronger, either of the compounds represented by Chemical Formula 1 becomes hole injection, hole transport, light emission. It can be a compound that satisfies the conditions as a material for electron injection or electron transport more appropriately.

For example, when Ar ₂ and Ar ₃ are substituted with a heteroarylamine group, the compound represented by Chemical Formula 1 has a wide range of applications such as a material for a hole injection layer (HIL) and a hole transport layer (HTL).

On the other hand, when Ar ₂ and Ar ₃ are substituted with a material having excellent electron affinity such as a heteroaryl group, the compound represented by Chemical Formula 1 is applied as an electron injection layer or electron transport layer (ETL) material. obtain.

Furthermore, when Ar ₁ is substituted with a substituent such as a phenyl group, naphthyl group, anthracenyl group, phenanthrenyl group, pyrenyl group, perylenyl group, chrysenyl group, etc., the thermal stability or oxidation resistance can be increased. , Ar ₂ or Ar ₃ can be substituted with a heteroarylamine group and a heteroaryl group substituent at the same time to provide an amphiphilic material, which can be applied to a light emitting layer.

As described above, compounds having various energy band gaps can be synthesized by introducing various substituents at the positions of Ar _{1 to} Ar ₃ in Chemical Formula 1.

  Therefore, the compound represented by Formula 1 is a compound that satisfies the requirements for the hole injection layer (HIL), the hole transport layer (HTL), the light emitting layer, the electron injection layer, and the electron transport layer due to various substituents. Can be.

  By selecting a compound having an appropriate energy level according to the substituent of compound 1 and applying it to an organic electronic device, a device with low driving voltage and high light efficiency can be achieved.

  Specific examples of the compound represented by Formula 1 include the following compounds (1) to (90), but are not limited thereto.

  The organic photoelectric device material containing the above compound can play a role of hole injection, hole transport, light emission, or electron injection and / or electron transport, and can also serve as a light emitting host together with an appropriate dopant. it can. According to the embodiment of the present invention, when the compound for an organic photoelectric device is contained in an organic thin film layer, the lifetime and electrochemical stability and thermal stability of the organic photoelectric device can be improved. In order to improve the driving voltage, the driving voltage can be lowered.

  According to another embodiment of the present invention, an organic photoelectric device including the organic photoelectric device material is provided. Examples of the organic photoelectric element include an organic light emitting diode, an organic solar battery, an organic transistor, an organic photosensitive drum, and an organic memory element.

  In the case of organic solar cells, the new compounds of the present invention are included in the electrode or electrode buffer layer, which can increase quantum efficiency. In the case of an organic transistor, it can be used as an electrode material such as a gate or a source-drain electrode.

  Hereinafter, the organic light emitting diode will be described in more detail. According to another embodiment of the present invention, there is provided an organic light emitting diode comprising an anode, a cathode, and at least one organic thin film layer disposed between the anode and the cathode. The organic thin film layer includes the organic photoelectric element material.

  The organic thin film layer includes a light emitting layer; and a hole transport layer (HTL), a hole injection layer (HIL), an electron transport layer (ETL), an electron injection layer (EIL), a hole blocking layer, and a combination thereof. Selected from the group. At least one layer includes the organic photoelectric device material according to the present invention.

  1 to 5 are cross-sectional views of an organic light emitting diode including an organic photoelectric device material according to an embodiment of the present invention.

  Referring to FIGS. 1 to 5, the organic light emitting diodes 100, 200, 300, 400, and 500 according to an embodiment of the present invention include at least one organic thin film layer 105 disposed between the anode 120 and the cathode 110. including.

The anode 120 includes an anode material having a high work function so as to facilitate hole injection into the organic thin film layer. Examples of the anode material include metals such as nickel, platinum, vanadium, chromium, copper, zinc, and gold or alloys thereof; zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO). Metal oxides such as ZnO: Al or SnO ₂ : Sb; or combinations of oxides with oxides; or poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) ) Thiophene] (PEDT), conductive polymers such as polypyrrole and polyaniline, but are not limited thereto. Preferably, the anode includes a transparent electrode such as ITO (indium tin oxide).

The cathode 110 includes a cathode material having a low work function so as to facilitate injection of electrons into the organic thin film layer. Cathode materials include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead or alloys thereof; LiF / Al, Liq / Al, LiO _{2 / Al, LiF / Ca,} LiF / Al, and _BaF 2 / Ca is a multilayer material and the like such as, but not limited to. Preferably, the cathode includes a metal electrode such as aluminum.

  Referring to FIG. 1, the organic photoelectric device 100 includes an organic thin film layer 105 including only a light emitting layer 130.

  Referring to FIG. 2, the two-layer organic photoelectric device 200 includes an organic thin film layer 105 including a light emitting layer 230 including an electron transport layer (ETL) and a hole transport layer (HTL) 140. The light emitting layer 230 also functions as an electron transport layer (ETL), and the hole transport layer (HTL) 140 has excellent bonding properties with a transparent electrode such as ITO, or has excellent hole transport properties.

  Referring to FIG. 3, the three-layer organic photoelectric device 300 includes an organic thin film layer 105 including an electron transport layer (ETL) 150, a light emitting layer 130, and a hole transport layer (HTL) 140. The light emitting layer 130 is provided independently, and a layer having excellent electron transporting property or a layer having excellent hole transporting property is laminated separately.

  As shown in FIG. 4, the four-layer organic photoelectric device 400 includes an electron injection layer (EIL) 160, a light-emitting layer 130, a hole transport layer (HTL) 140, and holes for bonding to the anode of ITO. An organic thin film layer 105 including an injection layer (ETL) 170 is included.

  As shown in FIG. 5, the five-layer organic photoelectric element 500 includes an electron transport layer (ETL) 150, a light emitting layer 130, a hole transport layer (HTL) 140, and a hole injection layer (HIL) 170. It includes a thin film layer 105 and further includes an electron injection layer (EIL) 160 to achieve a low voltage.

  1 to 5, the electron transport layer (ETL) 150, the electron injection layer (EIL) 160, the light emitting layers 130 and 230, the hole transport layer (HTL) 140, the hole injection layer (HIL) 170, and these The organic thin film layer 105 including at least one selected from the group consisting of the above includes the organic photoelectric element material. The organic photoelectric device material may be used for an electron transport layer (ETL) 150 including an electron transport layer (ETL) 150 or an electron injection layer (EIL) 160. When used for an electron transport layer (ETL), an additional hole blocking layer (not shown) is not required, and thus an organic photoelectric device having a more simplified structure can be provided.

  In addition, when the organic photoelectric device material is included in the light emitting layers 130 and 230, the organic photoelectric device material may be included as a phosphorescent or fluorescent host or a fluorescent blue dopant.

  The organic light emitting diode described above forms an anode on a substrate; dry coating methods such as vacuum evaporation, sputtering, plasma plating, and ion plating; or spin coating, dipping. ), Forming an organic thin film layer by a wet coating method such as flow coating; and forming a cathode thereon.

  Another embodiment of the present invention provides a display device including the organic photoelectric device according to the above embodiment.

  The invention is explained in more detail using the following implementation. However, it will be understood that the invention should not be limited by these examples.

(Preparation of materials for organic photoelectric devices)
Synthesis Example 1: Synthesis of Compound (1) As a specific example of a material for an organic photoelectric device, compound (1) was synthesized in two steps according to the following reaction formula 1.

First stage: synthesis of intermediate product (A) 2,4,6-trichloropyrimidine 75.0 g (409 mmol), phenylboronic acid 54.8 g (450 mmol) and tetrakis- (triphenylphosphine) palladium 11.8 g ( 10 mmol) was suspended in a mixed solvent of 450 ml of tetrahydrofuran and 300 ml of toluene to obtain a suspension. This suspension was added to a solution of 113.0 g (818 mmol) of potassium carbonate in 300 ml of water, and the resulting mixture was heated to reflux for 9 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate.

  After the organic solvent was removed by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration, washed with toluene, and 64.7 g of intermediate product (A) (recovered). (Rate: 70.3%).

Second stage: Synthesis of compound (1) Intermediate product (A) 2.3 g (10 mmol), 2- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2) Suspension of 6.3 g (22 mmol) of -yl) phenyl) pyridine (B) and 0.6 g (0.5 mmol) of tetrakis- (triphenylphosphine) palladium in a mixed solvent of 70 ml of tetrahydrofuran and 50 ml of toluene Got. This suspension was added to a solution in which 5.7 g (41 mmol) of potassium carbonate was dissolved in 50 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate.

  After removing the organic solvent by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration, washed with toluene, and 3.9 g of compound (1) (yield: 67 0.9%).

¹ H NMR (300 MHz, CDCl ₃ ) 8.85 (d, 2H), 8.75 (d, 2H), 8.45 (d, 2H), 8.34 (d, 2H), 8.21 (m 4H), 8.08 (s, 1H), 7.80 (m, 4H), 7.60 (m, 3H), 7.27 (m, 2H); MS [M + 1] 463.

Synthesis Example 2: Synthesis of Compound (2) As a specific example of a material for an organic photoelectric device, compound (2) was synthesized in two steps according to the following reaction formula 2.

First Step: Synthesis of Intermediate Product (C) 75.0 g (409 mmol) of 2,4,6-trichloropyrimidine, 77.3 g (450 mmol) of naphthylboronic acid and 11.8 g of tetrakis- (triphenylphosphine) palladium ( 10 mmol) was suspended in a mixed solvent of 450 ml of tetrahydrofuran and 300 ml of toluene to obtain a suspension. This suspension was added to a solution of 113.0 g (818 mmol) of potassium carbonate in 300 ml of water, and the resulting mixture was heated to reflux for 9 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate.

  After removing the organic solvent by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration, washed with toluene, and 80.0 g of intermediate product (C) (recovered). Rate: 71.1%).

Second stage: Synthesis of compound (2) Intermediate product (C) 3.2 g (12 mmol), 2- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2) Suspension of 7.2 g (26 mmol) of -yl) phenyl) pyridine (B) and 0.7 g (0.6 mmol) of tetrakis- (triphenylphosphine) palladium in a mixed solvent of 100 ml of tetrahydrofuran and 65 ml of toluene Got. This suspension was added to a solution in which 6.4 g (47 mmol) of potassium carbonate was dissolved in 65 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate.

  After removing the organic solvent by distillation under reduced pressure, the residue was recrystallized with toluene, the precipitated crystals were separated by filtration, washed with toluene, and 4.1 g of compound (2) (yield: 69. 0%).

¹ H NMR (300 MHz, CDCl ₃ ) 8.85 (d, 2H), 8.76 (d, 2H), 8.45 (m, 3H), 8.20 (m, 4H), 8.01 (m 3H), 7.80 (m, 5H), 7.61 (m, 3H), 7.27 (m, 2H); MS [M + 1] 513.

Synthesis Example 3: Synthesis of Compound (10) As a specific example of a material for an organic photoelectric device, a compound (10) was synthesized according to the following reaction formula 3.

  Intermediate product (A) 2.3 g (10 mmol), 1- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl) isoquinoline (D) 7 0.5 g (22 mmol) and tetrakis- (triphenylphosphine) palladium 0.6 g (0.5 mmol) were suspended in a mixed solvent of 70 ml of tetrahydrofuran and 50 ml of toluene to obtain a suspension. This suspension was added to a solution in which 5.7 g (41 mmol) of potassium carbonate was dissolved in 50 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate.

  After the organic solvent was removed by distillation under reduced pressure, the residue was recrystallized with toluene, the precipitated crystals were separated by filtration, washed with toluene, and 3.9 g of compound (10) (yield: 68. 0%).

¹ H NMR (300 MHz, CDCl ₃ ) 8.94 (d, 2H), 8.68 (d, 2H), 8.52 (d, 2H), 8.39 (d, 2H), 8.21 (d 2H), 8.16 (s, 1H), 7.94 (m, 6H), 7.72 (m, 4H), 7.61 (m, 5H); MS [M + 1] 563.

Synthesis Example 4: Synthesis of Compound (11) As a specific example of a material for an organic photoelectric device, compound (11) was synthesized according to the following reaction formula 4.

  Intermediate product (C) 2.7 g (10 mmol), 1- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl) isoquinoline (D) 7 .2 g (22 mmol) and tetrakis- (triphenylphosphine) palladium 0.6 g (0.5 mmol) were suspended in a mixed solvent of 80 ml of tetrahydrofuran and 55 ml of toluene to obtain a suspension. This suspension was added to a solution of 5.4 g (39.1 mmol) of potassium carbonate in 55 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate.

  After the organic solvent was removed by distillation under reduced pressure, the residue was recrystallized with toluene, the precipitated crystals were separated by filtration, washed with toluene, and 4.5 g of compound (11) (yield: 65. 0%).

¹ H NMR (300 MHz, CDCl ₃ ) 8.93 (d, 2H), 8.67 (d, 2H), 8.53 (d, 2H), 8.45 (d, 1H), 8.21 (d 2H), 7.96 (m, 10H), 7.72 (m, 5H), 7.64 (m, 4H); MS [M + 1] 613.

Synthesis Example 5: Synthesis of Compound (19) As a specific example of a material for an organic photoelectric device, a compound (19) was synthesized according to the following reaction formula 5.

  Intermediate product (A) 4.0 g (18 mmol), 3- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl) quinoline (E) 13 0.0 g (39 mmol) and 1.0 g (0.9 mmol) of tetrakis- (triphenylphosphine) palladium were suspended in a mixed solvent of 120 ml of tetrahydrofuran and 80 ml of toluene to obtain a suspension. This suspension was added to a solution obtained by dissolving 9.8 g (71 mmol) of potassium carbonate in 80 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate.

  After the organic solvent was removed by distillation under reduced pressure, the residue was recrystallized with toluene, the precipitated crystals were separated by filtration, washed with toluene, and 6.5 g of compound (19) (yield: 64. 7%).

¹ H NMR (300 MHz, CDCl ₃ ) 9.31 (d, 2H), 8.89 (d, 2H), 8.40 (m, 6H), 8.17 (d, 2H), 8.09 (s) 1H), 7.92 (m, 6H), 7.75 (m, 2H), 7.59 (m, 5H); MS [M + 1] 563.

Synthesis Example 6: Synthesis of Compound (63) As a specific example of a material for an organic photoelectric device, a compound (63) was synthesized according to the following reaction formula 6.

First Step: Synthesis of Intermediate Product (F) Carbazole 50.8 g (304 mmol), 1,4-dibromobenzene 71.6 g (304 mmol), cuprous chloride 3.76 g (38 mmol), and potassium carbonate 83. 9 g (607 mmol) was suspended in 322 ml of dimethyl sulfoxide and refluxed for 8 hours with heating under a nitrogen atmosphere. The resulting reaction fluid was cooled to room temperature and recrystallized using methanol.

  The obtained crystals were separated by filtration, and the obtained product was purified using silica gel column chromatography to obtain 55.9 g of intermediate product (F) (yield: 61.3%).

Second Step: Synthesis of Intermediate Product (G) 37.8 g (117 mmol) of the intermediate product (F) was dissolved in 378 ml of tetrahydrofuran, and an n-butyllithium hexane solution (1. 6M) 100.5 ml (161 mmol) was added and then the resulting solution was stirred at -70 to -40 ° C for 1 hour. After cooling the reaction fluid to −70 ° C., 47.9 ml (235 mmol) of isopropyltetramethyldioxaborolane was added dropwise. The resulting solution was stirred at -70 ° C for 1 hour, then warmed to room temperature and stirred for 6 hours. 200 ml of water was added to the resulting solution and stirred for 20 minutes.

  After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate.

  After the organic solvent was removed by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration, washed with toluene, and 28.9 g of intermediate product (G) (recovered). Rate: 66.7%).

Third stage: Synthesis of intermediate product (H) 26.8 g (73 mmol) of intermediate product (G), 20.0 g (73 mmol) of compound (C) and 2.1 g of tetrakis- (triphenylphosphine) palladium ( 1.8 mmol) was suspended in a mixed solvent of 600 ml of tetrahydrofuran and 400 ml of toluene to obtain a suspension. This suspension was added to a solution of 20.1 g (154 mmol) of potassium carbonate in 400 ml of water, and the resulting mixture was heated to reflux for 8 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate.

  After removing the organic solvent by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration, washed with toluene, and 23.0 g of intermediate product (H) (recovered). (Rate: 65.4%).

Fourth Step: Synthesis of Compound (63) Intermediate Product (H) 6.0 g (12 mmol), Compound (E) 4.5 g (14 mmol) and Tetrakis- (triphenylphosphine) palladium 0.36 g (0.3 mmol) ) Was suspended in a mixed solvent of 180 ml of tetrahydrofuran and 120 ml of toluene to obtain a suspension. This suspension was added to a solution in which 3.4 g (25 mmol) of potassium carbonate was dissolved in 120 ml of water. The resulting mixture was heated to reflux for 12 hours. After separating the reaction fluid into two layers, the organic layer was washed with a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate.

  After removing the organic solvent by distillation under reduced pressure, the residue was recrystallized with toluene, and the obtained crystals were separated by filtration and washed with toluene to give 7.2 g of Compound (63) (Yield: 88 .3%) was obtained.

¹ H NMR (300 MHz, CDCl ₃ ) 9.31 (s, 1H), 8.92 (d, 2H), 8.62 (d, 2H), 8.45 (m, 2H), 8.19 (d 3H), 7.71 (m, 20H); MS [M + 1] 651.

  The glass transition temperature and thermal decomposition temperature of the synthesized compound were determined by measuring by differential scanning calorimetry (DSC) and thermogravimetry (TGA). The result of the compound (1) according to Synthesis Example 1 is shown in FIG.

(Manufacture of organic photoelectric devices)
Example 1
A 15 Ω / cm ² (1200 mm) ITO glass substrate manufactured by Corning. Inc. was cut into a size of 50 mm × 50 mm × 0.7 mm and ultrasonically cleaned in isopropyl alcohol and pure water for 5 minutes each. Thereafter, UV and ozone cleaning was performed for 30 minutes.

  On the surface of the glass substrate, N, N′-diphenyl-N, N′-bis- [4- (phenyl-m-tolylamino) -phenyl)]-biphenyl-4,4′-diamine (N, N′- diphenyl-N, N'-bis- [4- (phenyl-m-tolyl-amino) -phenyl] -biphenyl-4,4'-diamine: DNTPD) (40 nm), N, N'-di (1-naphthyl) ) -N, N′-diphenylbenzidine (NPB) (10 nm), EB-46 (fluorescent blue dopant manufactured by E-Ray Optoelectronic Technology): EB-512 (blue manufactured by Elay Optoelectronic Technology) Fluorescent host) 6% (40 nm) and compound (1) (10 nm) obtained in Synthesis Example 1 were heated in order. Evaporation to a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer was formed, and the electron transport layer (ETL).

  On the ETL, LiF was vacuum-deposited as an electron injection layer (EIL) to a thickness of 0.5 nm, and Al was vacuum-deposited to a thickness of 100 nm to form a LiF / Al electrode. The structure of the obtained organic photoelectric device is shown in FIG.

Example 2
An organic photoelectric device was produced in the same manner as in Example 1 except that the compound (2) (10 nm) obtained in Synthesis Example 2 was used instead of the compound (1).

Example 3
An organic photoelectric device was produced in the same manner as in Example 1 except that the compound (10) (10 nm) obtained in Synthesis Example 3 was used instead of the compound (1).

Example 4
An organic photoelectric device was produced in the same manner as in Example 1 except that the compound (11) (10 nm) obtained in Synthesis Example 4 was used instead of the compound (1).

Example 5
An organic photoelectric device was produced in the same manner as in Example 1 except that the compound (19) (10 nm) obtained in Synthesis Example 5 was used instead of the compound (1).

Example 6
An organic photoelectric device was produced in the same manner as in Example 1 except that the compound (63) (10 nm) obtained in Synthesis Example 6 was used instead of the compound (1).

Comparative Example 1
An organic photoelectric device was produced in the same manner as in Example 1 except that Alq ₃ (10 nm), which is a compound represented by the following chemical formula 2, was used instead of the compound (1).

Measurement of performance of organic photoelectric device The luminous efficiency by voltage was measured for each of the organic photoelectric devices manufactured in Examples 1 to 6 and Comparative Example 1. The measurement method is as follows.

1) Measurement of change in current density due to voltage change For each of the organic photoelectric devices prepared in Examples 1 to 6 and Comparative Example 1, the voltage was increased from 0V to 14V, and a current-voltmeter (Keithley 2400). (Registered trademark)) was used to measure the current value flowing through the unit element. These current densities were measured by dividing the current value by the area.

2) Measurement of luminance change due to voltage change For each organic photoelectric element according to Examples 1 to 6 and Comparative Example 1, the voltage was increased from 0 V to 14 V, and a luminance meter (Minolta Cs-1000A) was used. The brightness was measured.

3) Measurement of power efficiency (luminous efficiency) Current density and luminance measured in “1) Measurement of change in current density due to voltage change” and “2) Measurement of change in luminance due to voltage change”, and voltage (V ) To calculate the power efficiency (luminous efficiency). The results are shown in Table 1 below.

Referring to Table 1, compared with the case where Alq _{3 of} Comparative Example 1 is used as the electron transport layer, the organic photoelectric elements of Examples 1 to 6 in which the electron transport layer was formed using the organic photoelectric element material according to the present invention. It can be seen that the device has excellent power efficiency (lm / W) with low drive voltage. Therefore, the organic compound according to an embodiment of the present invention has high thermal stability, and, as can be seen from the performance evaluation results of the organic photoelectric device, has a low driving voltage and high light emission efficiency. It is expected that it can be improved. It is thought that the asymmetry of the organic photoelectric device material enhances the amorphous characteristics, which suppresses crystallization and improves the lifetime of the device.

4) Measurement of thermal characteristics The compounds obtained in Synthesis Examples 1 to 6 are subjected to a primary analysis by differential scanning calorimetry (DSC), and then a secondary analysis is performed on the compounds after the primary analysis. It was. The analysis results for the compound of Synthesis Example 1 are shown in FIG. Referring to FIG. 6, the compound of Synthesis Example 1 showed a melting point peak in the primary analysis but did not show a melting point peak in the secondary analysis. From this result, it was confirmed that the compound of Synthesis Example 1 exists in a stable amorphous state.

  In addition, it was confirmed that the compounds of Synthesis Examples 2 to 6 exist in an amorphous state by the same method. Therefore, it is predicted that the organic light-emitting diodes containing the compounds of Synthesis Examples 1 to 6 exhibit improved lifetime characteristics as compared with existing organic photoelectric elements without being affected by Joule heat during driving.

  The present invention is not limited to the above-described embodiments, but can be produced by those skilled in the art in various modifications and equivalent forms included in the spirit and technical scope of the claims. Therefore, it should be understood that the above examples are illustrative and do not limit the invention in any way.

Claims (14)

A material for an organic photoelectric device including an asymmetric compound represented by the following chemical formula 1:
In Formula 1,
Ar ₁ is selected from the group consisting of hydrogen and a substituted or unsubstituted aryl group, provided that when Ar ₁ is a substituted aryl group, the substituent of Ar ₁ is not the same as Ar ₂ ;
Ar ₂ and Ar ₃ are each independently a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 2 to 30 carbon atoms, and Selected from the group consisting of substituted or unsubstituted heteroarylamine groups having 2 to 30 carbon atoms;
L ₁ and L ₂ are each independently selected from the group consisting of substituted or unsubstituted phenylene, substituted or unsubstituted naphthylene, and substituted or unsubstituted anthracene;
m and n are integers of 1 to 4. The material according to claim 1, wherein Ar ₁ is selected from the group consisting of a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, and a chrysenyl group. Ar ₁ is an alkyl group having 1 to 30 carbon atoms, a heteroalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an alkoxy group having 1 to 30 carbon atoms. The material according to claim 1, wherein the material is substituted with a substituent selected from the group consisting of: Ar ₂ and Ar ₃ are each independently imidazolyl group, thiazolyl group, oxazolyl group, oxadiazolyl group, triazolyl group, pyridinyl group, pyridazine group, quinolinyl group, isoquinolinyl group, acridyl group, imidazopyridinyl group, imidazolpyrimidinyl group Selected from the group consisting of: a diphenylamine group, a dinaphthylamine group, a dibiphenylamine group, a phenylnaphthylamine group, a phenyldiphenylamine group, a ditolylamine group, a phenyltolylamine group, a carbazoyl group, a triphenylamine group, and a dipyridylamine group. Item 2. The material according to Item 1. The material of claim 1, wherein L ₁ and L ₂ are phenylene. 2. The material according to claim 1, wherein the compound represented by Chemical Formula 1 includes the following compounds (1) to (90) or a combination thereof.
An anode; a cathode; and at least one organic thin film layer disposed between the anode and the cathode;
At least 1 is an organic photoelectric element containing the material for organic photoelectric elements of any one of Claims 1-6 among the said organic thin film layers.   The organic thin film layer is at least one selected from the group consisting of a light emitting layer; and a hole transport layer (HTL), a hole injection layer (HIL), an electron injection layer (EIL), a hole blocking layer, and combinations thereof. The organic photoelectric element of Claim 7 containing two layers.   The organic photoelectric element according to claim 7, wherein the organic photoelectric element material is contained in an electron transport layer (ETL) or an electron injection layer (EIL).   The organic photoelectric element according to claim 7, wherein the organic photoelectric element material is included in a light emitting layer.   The organic photoelectric device according to claim 7, wherein the organic photoelectric device material is contained in the light emitting layer as phosphorescent or fluorescent host.   The said organic photoelectric element material is an organic photoelectric element of Claim 7 contained as a blue fluorescence dopant in a light emitting layer.   The organic photoelectric element according to claim 7, which is selected from the group consisting of an organic light emitting diode, an organic solar cell, an organic transistor, an organic photosensitive drum, and an organic memory element.   A display device comprising the organic photoelectric element according to claim 7.